Prerequisites
🚀 Feature Proposal
Problem
When using fastify-type-provider-typebox, union type validation failures provide minimal error details:
{
message: 'Expected union value',
instancePath: ''
}This lacks the detailed validation information that TypeBox provides through its errors property in the ValueError interface, making it difficult for developers to debug union-type validation failures.
Background
TypeBox's ValueError interface contains rich error information:
export interface ValueError {
type: ValueErrorType;
schema: TSchema;
path: string;
value: unknown;
message: string;
errors: ValueErrorIterator[]; // Contains detailed validation results for each union member
}Current error mapping in fastify-type-provider-typebox:
error: errors.map((error) => ({
message: `${error.message}`,
instancePath: error.path
}))Proposal
Enhance the error mapping to include detailed union validation information:
import { TypeCompiler, ValueError, ValueErrorIterator } from '@sinclair/typebox/compiler';
import { Type } from '@sinclair/typebox';
const CreateActionDelayBody = Type.Object({
action: Type.Literal('DELAY'),
days: Type.Number(),
});
const CreateActionSMSBody = Type.Object({
action: Type.Literal('SMS'),
phone: Type.String(),
});
const CreateActionEmailBody = Type.Object({
action: Type.Literal('EMAIL'),
email: Type.String({ format: 'email' }),
});
const CreateActionBody = Type.Union([
CreateActionDelayBody,
CreateActionSMSBody,
CreateActionEmailBody,
]);
const C = TypeCompiler.Compile(CreateActionBody);
type ReducedError = [{ message: string; path: string; errors: ReducedError[] }];
const MapValueIterator = (iterator: ValueErrorIterator): ReducedError[] =>
[...iterator].map((error) => MapValueError(error)) as never;
const MapValueError = (error: ValueError) => ({
message: error.message,
path: error.path,
errors: error.errors.map((iterator) => MapValueIterator(iterator)),
});
const value = { action: 'ONE' };
const R = MapValueIterator(C.Errors(value));
console.dir(R, { depth: 100 });Example Output
[
{
"message": "Expected union value",
"path": "",
"errors": [
[
{
"message": "Expected required property",
"path": "/days",
"errors": []
},
{ "message": "Expected 'DELAY'", "path": "/action", "errors": [] },
{ "message": "Expected number", "path": "/days", "errors": [] }
],
[
{
"message": "Expected required property",
"path": "/phone",
"errors": []
},
{ "message": "Expected 'SMS'", "path": "/action", "errors": [] },
{ "message": "Expected string", "path": "/phone", "errors": [] }
],
[
{
"message": "Expected required property",
"path": "/email",
"errors": []
},
{ "message": "Expected 'EMAIL'", "path": "/action", "errors": [] },
{ "message": "Expected string", "path": "/email", "errors": [] }
]
]
}
]I understand we need to stick to FastifySchemaValidationError. I'm raising this here to discuss how to better support it.
Motivation
No response
Example
No response
Prerequisites
🚀 Feature Proposal
Problem
When using
fastify-type-provider-typebox, union type validation failures provide minimal error details:This lacks the detailed validation information that TypeBox provides through its
errorsproperty in theValueErrorinterface, making it difficult for developers to debug union-type validation failures.Background
TypeBox's
ValueErrorinterface contains rich error information:Current error mapping in
fastify-type-provider-typebox:Proposal
Enhance the error mapping to include detailed union validation information:
Example Output
[ { "message": "Expected union value", "path": "", "errors": [ [ { "message": "Expected required property", "path": "/days", "errors": [] }, { "message": "Expected 'DELAY'", "path": "/action", "errors": [] }, { "message": "Expected number", "path": "/days", "errors": [] } ], [ { "message": "Expected required property", "path": "/phone", "errors": [] }, { "message": "Expected 'SMS'", "path": "/action", "errors": [] }, { "message": "Expected string", "path": "/phone", "errors": [] } ], [ { "message": "Expected required property", "path": "/email", "errors": [] }, { "message": "Expected 'EMAIL'", "path": "/action", "errors": [] }, { "message": "Expected string", "path": "/email", "errors": [] } ] ] } ]I understand we need to stick to FastifySchemaValidationError. I'm raising this here to discuss how to better support it.
Motivation
No response
Example
No response